Encephalitozoon hellem in two eclectus parrots (Eclectus roratus): identification from archival tissues

Members of the phylum Microspora are obligate, intracellular, single-celled parasites identified in a wide range of vertebrate and invertebrate hosts. Only a few cases of microsporidial infections have been documented in psittacine birds including peach-faced, masked, and Fischer's lovebirds (Agapornis roseicollis, A. personata, and A. fischeri, respectively), budgerigars (Melopsittacus undulatus), and a double yellow-headed Amazon parrot (Amazona ochrocephala). Parasite identification has typically been limited to phylum or genus, and no avian species of microsporidia has clearly been described. In this report, microsporidia were identified in the kidney and intestine of a new host, the eclectus parrot (Eclectus roratus). Parasites were identified as Encephalitozoon hellem using morphologic, ultrastructural, and small subunit ribosomal RNA gene sequence data obtained from archived tissues. This parasite species was first identified in immunocompromised humans and may be a potential zoonotic pathogen. The epidemiology and prevalence of this parasite in humans and birds should be further explored.